Hydraulic power unit



ept- 1940. E. M. PFAUSER. 2,214,257

HYDRAULIC POWER UNIT Filed Aug. 2, 1937 s Shoots-Sheet 1 ATTORNEY.

Sept. 10, 1940.

E. M. PFAUSER 2,214,257

HYDRAULIC POWER mm Filed Aug. '2, 1937 Shoots-Sheot 2' v I INVENTOR. Ifg; 7o I Emma \Z\?Kww ATTORNEY.

Patented Sept. 10, 1940 UNITED STATES 2,214,257 nymmuuc rowan UNIT Edward M. Piauser, Elm Grove, Wis., assignor to Blackhawk Mfg. (220.,- Milwaukee, Wis., acorporation of Wisconsin Application August 2, 1937, Serial No. 156,860

3 Claims.

This invention relates to an improvement in hydraulic power umts of the type wherein the pump, release valve and reservoir are incorporated in one unit, from which the liquid, usually an, is

5 pumped through flexible hose or tubing to one or more rams located at points remote from the unit.

' Generally speaking, the object of the invention is to simplify and compact the construction 10 of a unit of this character, improve its appearance, facilitate its operation and enhance its emciency, its-capacity for its intended use and its adaptability for a variety of applications.

More specific objects of theinvention are to 15 minimize the possibility of oil leakage and reduce to a minimum the disadvantage of any leakage that does occur; provide for positive pump operation and a positive pressure drive at all handle or lever speeds; prevent the possibility of air being drawn into the pump on its suction stroke and consequent air binding; so control the ram lowering operation as to prevent, for all practical purposes, its accidental or unintentional operation; render the various elements of the 25 unit readily accessible for purposes of adjustment, replacement or repair and this without loss of oil; construct the unit externally as to avoid the accumulation of dirt, snow or water thereon 30 and preclude the possibility of the operating handle or lever freezing in place; and make practical the installation and the convenient operation of the unit in any one of a plurality of difierent positions.- I

35 In carrying out the present invention, the hydraulic power unit is made up of two main elements, namely, a reservoir and a head. The reservoir contains the supply of oil and has a single opening in what is ordinarily its top wall.

40 In the assembly, the head is releasably secured to the reservoir and closes and seals its opening. The pump, the operating means therefor, the intake and outlet' ordelivery pipes, the passages through which the oil flows from the intake pipes to the pump and from the pump to the outlet or delivery pipes, the valves which regulate the oil flow through these passages, the return passage from the outlet pipe to the reservoir and the release valve which controls the flow through the return passage to the reservoir are all combined with the head and constitute one unitary structure which'may be applied to and removed from tlie reservoir as a unit. elf-eases and intact more than doubles the oil .55 capacity of the unit and makes it convenient to This construction in-* interchangeably employ pump and control instrumentalities of various types and sizes. To adapt the unit for convenient installation in crowded quarters, the head is interrelated with the reservoir for angular adjustment and these parts may be releasably secured together in any one of a plurality of different relative angular positions. Furthermore, the intake pipes are so related to the reservoir and so combined with the head and the unit is-otherwise so constituted that while the unit may be and usually is mounted upright, that is, with the head at the top of the reservoir, it also may be turned over on one side with the head vertically disposed; and yet the intake pipes extend to the low point in the reservoir and the unit may be conveniently operated in both positions.

The pump is combined in a special way with the head in that the cylinders are disposed on the inner side of the head and within the confines of the space enclosed by the reservoir and head. Hence should any leakage from the cylinders occur, the leaking oil will drain back into the reservoirand wil lnot be lost and incidentally will not dirty orsoil the unit or its environment. In fact, 5 with the various elements of the unit built into the head in the manner described the number of. threaded connections under pressure and ext'eriorly exposed are reduced to a minimum and such as are employed are'with the head, hence above the oil level in the reservoir, and are readily made liquid tight.

Where the unit is to be employed to serve selectively a plurality of rams the head is designed to be connected up' with the requisite number of outlet or delivery pipes, communication of which with the common outlet passage from the pump is controlled by individual manually operable valves. v

Other objects and advantages reside in certain 40 novel features of the construction, arrangement and combination of parts which will be hereinafter more fully described and particularly pointed out in the appended claims, reference being had to the accompanying drawings forming. a part of this specification and in which:

Figure 1 is aviewin top plan showing a hydraulic power unit embodying the present invention;

Figure .2 is a view in longitudinal vertical section taken on line 2-2 of Figure 1, parts being broken away and parts being shown in elevation for the sake of simplicity in illustration;

Figure 3 is a fragmentary sectional view taken on line 3-3 of Figure 1 with parts shown in elevation for the sake of illustration; 66

Figure 4 is a view in top plan of the head of the unit and a fragment of the outlet or delivery pipe connected therewith and illustrating the passages in the head in dotted lines;

Figure 5 is a view in bottom plan of the head of the unit with a similar showing of the passages and with the intake pipes shown in cross section;

Figure 6 is a view illustrating the head of the unit and its intake pipes in end elevation and showing the reservoir in transverse vertical sec- "tion;

Figures 7 and 8 are fragmentary views in vertical cross section taken on lines 1- 1 and 8-'8 respectively of Figure 4; parts being shown in endelevation for the Sake of illustration;

Figure 9 is a view in horizontal cross section taken on line 9-9 of Figure 6 and illustrating the construction of the cylinders and the passages leading thereto;

Figure 10 is a group view in perspective illustrating the double plunger, the rocker arm which actuates the same and a fragment of the operating lever;

Figure 11 is a view in top plan showing a modifled form of head designed to be employed with a unit of this type where the unit serves a plurality of rams; Figures 12, 13, 14 and 15 are viewsin vertical section takenon lines l2.|2, l3--l3, "-44, and |5l5 of Figure 11; and

Figure 16 is a view in end elevation of this modified form of head.

Referring to the drawings and more particularly to Figures 1 to 10 inclusive it will be seen that the hydraulic power unit there shown comprises generally a reservoir R and a head H. I

The reservoir R comprises a metal receptacle of oblong form comprising a bottom wall I, a vertical peripheral wall 2 integral therewith and a horizontal top wall 3 provided with a central opening I and formed with an annular flange 4 around the margin ofthe opening. Apertured attaching flanges 5 may be integrally formed with the reservoir tofacilitate the mounting and securement of the reservoir in point of use.

The head I-I comprises a casting which lit-the structure shown is of circular outline, is formed with an inset and downwardly projecting peripheral wall 6 designed to snugly fit into the flanged opening I and with an outwardly extending annular flange I which overlies the top of. the flange l and is releasably secured thereto in any suitable way, as for example, by screws 8. A gasket 9'is interposed between the flanges 4 and 'l so that when the head is applied and fastened down it serves to close the opening 6' and seal the reservoir. With this construction'the head may be angularly adjusted with respect to the, reservoir and by providing the flange .4 with a greater number of openings or bolt holes l2 than; the flange 1 it is practical to releasably secure the head H in any one of a number of different angular positions relative to the reservoir. This is advantageous when mounting the unit incrowded quarters.

.f- Integral with the underside of the head H are axially spaced and alined cylinders 16 and ll.

The cylinders are open ended but in the assembly their outer ends are closed'and sealed by plugs I 2 threadedly connected therewith as shown in the drawings. However, should any oil leak past the plugs it is apparent that it will find its way back into the reservoir since the cylinders and their plugs are entirely contained in the space position at the with an internally threaded socket into which 'plish this intake pipes3'l and 38 the intake pipes having their upper enclosed by the reservoir-R and head H. A wall or web I3 is integral with the inner or adjacent endsof the cylinders l6 and II and with the head and coacts with the head to define a chamber or well ll closed at its bottom and at its sides although directly communicating with opening l5 which extends up through the top of the head.

A double plunger designated generally at I6 is operatively fitted in the cylinders l0 and H, the plunger including plunger members I! and I8 and a notched or flattened connecting portion 49 integral with these plunger members. Each plunger member has its outer end provided with a reduced extension 20. On each reduced extension 20 a packing cup 2| is fitted. The outer portion of each reduced extension is threaded and with this threaded portion nuts 22 are engaged, the inner nut pressing against a metallic spreader 23 interposed between the inner nut 22 and the adJacent face of the cup 2 I. V

For the purpose of reciprocating the plunger in the cylinders l6 and H a rocker arm designated generally at 25 is provided and has a ball 26 engaging a seat 21 which is supported on a shoulder 26 formed at the juncture of the opening l5 and space I 4. The inner end of the rocker arm is bifurcated as at 29 and its spaced arms 30 straddle the notched or flattened connecting portion I 9 of the plunger l6. At the Junctures of the connecting portion l9 and the plunger members I! and I8 shoulders 3| are presented and when the rocker arm is assembled with this plunger the rounded faces 3ll' of its arms 30 bear against these shoulders. The ball 26 is held in 7 stantially flush with the adjacent portion of the top of the head and eliminates the deep well effect and hence prevents the accumulation of dirt, water, snow or ice and avoids-the possibility of the operating lever or handle freezing in place.

The outer portion of the ball 26 is provided the lower threaded end of an operating lever or handle is threaded in the assembly. The outer end of the lever 35 may be equipped with a knob 36 after'the manner of a gear shift lever. The knob 36 fits the hand and together with the ball and socket mounting or fulcrum for the lever 35 makes pumping easier.

:With this construction, when the lever 35 is rocked, the plunger I6 is reciprocated to cause the pump todraw oil from the reservoir to force it under pressure to the ram or rams in a manner which hereinafter will more clearly appear.

The outer ends of the cylinders draw their oil from a low point in the reservoir and to accomare provided, ends threadedly connected with the underside of the head H adjacent to but laterally ofi'set from the cylinders "and II- respectively and in direct communication with vertical passages in the head (see gure 3).

As shown in Figures 2, 3, 6 and '7 the intake pipes 31 and 38 are angled so as to extend from the head H down to a pointadjacent one of the bottom corners of the reservoir. This so disposes the lower extremities of the intake pipes that they are located at the low point of the reservoir not only when the unit is positioned upright but also when it is turned over on one of its sides.

39 and 40 provided latlng the action of the twin pumps are located in the vertical passages 39 and 40 and as they are identical a single description will serve for both. As shown to advantage in Figure 3 suc-' tion valves 4| are provided in the passages 39 and 40 and preferably are the simple ball valves biased to engage their seats under the influence of gravity. The discharge valves 42 are also ball valves and are located in the passages 39 and 40 above the suction valves 4|. These discharge valves 42 are biased into engagement with their seats by gravity and also by means of light coil springs 43, the lower ends of which bear down against the discharge valves and the upper ends of which abut cap screws 44 threaded into the enlarged upper ends of the passages 39 and for closing and sealing the same. By removing the screws 44 access is readily had to the suction and discharge valves.

, with horizontal passages 45 and 46 (see Figure 9). These passages 45 and 46 extend from the passages 39 and 40 to the outer ends of the cylinders Ill and I respectively and are in direct communication with these cylinders. Above the discharge valves 42 the passages 39 and 4|! are cross connected by a main outlet passage 47, the ends of which are closed in the manner illustrated in Figure 3.

From the main outlet passage 41 the oil is conducted either to a ram or is returned back to the reservoir and for this purpose the main outlet passage 41 adjacent one of its ends is in open communication with an inclined and transversely extending passage 48 (see Figures 2, 3 and 4) which leads to an opening 49 formed in a boss 50 provided on the upper side of the head. An outlet pipe 5| is threadedly connected with the boss 50, freely communicates with the opening s9 and extends to the ram (not shown) which the unit operates; The other end of the main outlet passage 41 is .in open communication with a passage 52 (see Figures 2, 3, 4, 6 and 8) which is also inclined and extends transversely of the head and communicates with .axial passage 53 formed in a boss 54 also integrally formed with .the head. The axial passage 53 leads to the valve seat 55 of a release valve designated generally at 55. Beyond the valve seat 55 the boss 53 is formed with an opening 53' suitably machined to accommodate the release valve 56. The opening 53' in the boss 54 on the other side of the release valveseat from the passage 53 communicates'with areturn duct or return passage 57 which extends down through the underside of the head and opens into the reservoir.

The release valve 56 comprises a, spindle 58 threadedly engaged with a packing nut 59 which is also threaded into the boss 54. Valve head 60 of release valve 56 is engageable with the seat 55.

The nut 59 not only serves 'as a threaded bearing from the spindle 58 of the release valve but also functions to compress the release valve packing 6|; An operating lever 62 is releasably secured to the outer end of the valve spindle 58 and members, for example the plunger member I8,

will draw oil into its cylinder while its other plunger member I1 is expelling oil from the cylinder M which has previously been drawn thereto. 0n the suction stroke of the plunger member l8 oil is pulled up through the intake pipe 38 and vertical passage 40' past the suction valve 4| and through the horizontal passage 46 into the cylinder II, the discharge valve 42 in passage 40 remaining closed during this phase of the operation under the influence of its bias and of pressure. On the return stroke of the .plunger member I8 the oil inthe cylinder H is expelled out through the passage 46 and up past the discharge valve 42 in passage 40, pressure and gravity maintaining the suction valve 4| in the passage 40 closed at this time. The oil forced up past either discharge valve 42 flows into the main outlet passage 41 and if the release valve 56 is closed it will flow through the passage 52, opening 50, and delivery pipe 5| to the ram. When the release valve is open oil will flow from the main outlet passage 41 through the passages 52 and 53 to the return passage 51 and will drain back into. the reservoir. Since the delivery pipe 5| to the ram is in free communication with the outlet passage 41 theram will be lowered when the release valve 56 is opened.

When the unit is in use the space |4-is partially filled with oil and in this way leakage of air past either plunger member on their suction strokes is prevented. An overflow opening l4 prevents pressures from building up in the space l4.

When the device is not in use the handle 35 and the lever 62 may be readily removed to preclude the possibility of unauthorized person's operating the unit.

In Figures 11 to 16 inclusive a modified head .structure designated generally at H' is shown a plurality of rams selectively or simultaneously.

The'head H like the head H is circular in outline and is designed to be bolted or releasablysecured to themarginal ,flange of the opening in the top of the reservoir.

Where the parts of the head H are identical with those of the head H they are designated by the same reference numeral. Thus it will be seen. that the head H has cylinders l0 and H integrally formed with its undersidewith the adjacent ends of the cylinders connected by the web or wall I 3. A double plunger I6 is operatively interrelated with the cylinders Ill and H and socket mounting in the central portion of the head asbefore. The oil is supplied to the outer ends of the cylinders through intake pipes 33 and 38 which are connected to the lower ends of the vertical passages designated in this form at 39 and 30 for the reason that they are somewhat longer than the' corresponding passages 39 and 40 in the head H due to the increased vertical dimensions of the head H. However, suction and discharge valves 4| and 42 are combined with these passages 33 and 40' in just the mannerabove described andthese passages 39' and 30 have their portions located between the valves connected to the outer ends of the cylinders by horizontal passages 45 and 46 and above the discharge valves 32 passages 39 and 40' communicate with a main outlet passage designated at -41. The discharge valve springs designated at 43 are somewhat longer then corresponding springs 43.

' This modified head also has the same release valve 56 combined therewith in the manner above described and regulatingthe return of the oil and is actuated by a hand lever 35 having a ball from the main outlet passage back to the reservoir through a return passage 51 as before.

The principal difference between the head H and the head H resides in the fact that the head H' has a plurality of outlet fittings designated at 10, IL 13 and-14 located at spaced points around its periphery and designed to be coupled by suitable pipes or tubing to separate rams.

In the head H branch outlet passages. connect the main outlet passage 41' with the outlet fittings 10, H, 12, I3 and 14 but the communication of these branch outlet passages with their respective outlet fittings is controlled by hand operated valves l5, I6, I1, 18 and 18 there being one such valve for each outlet fitting. As illustrated in Figures 11 and 14 an intermediate portion of the main outlet passage 41' connects with one end of a radially extending branch passage and the outer end of this branch passage 80 connects with the lower-end ofv a vertically extending passage the upper end of the passage 8| in turn connecting with a transversely extending passage 82 the ends of which terminate in valve chambers 83 of the valves 15 and 16 at points above the valve seats of said chambers.

As shown in Figures 11, 15 and 16 a branch passage extends from one end portion of the main outlet passage 41' up to the passage 53 leading to the release valve and the upper end of this passage 85 also communicates with an inclined passage 86 which leads into the valve chamber of. the valve 12 above the valve seat thereof. Branch passages 8'l and 88 which are in effect continuations of the branch passage 86 similarly communicate with the valve chambers of the valves 18 and 19.

The valves 15, 16, l1, l8 and 19 are all identical in construction so that a single description will serve for all. Each of these valves has a casing 90 formed integral with the head and provided with the valve chamber 9| with which the branch passages communicate, a valve seat 92 at the lower end of this chamber and a short vertical passage 93 leading from the valve seat down to the associated-outlet fitting (see Figures 12 and 15). Each valve has a stem 94 provided at its lower end with a beveled head 95 engageable with its valve seat. The upper end of each stem is provided with a hand wheel 96. A portion of the stem is externally threaded as at 91 and engaged with the internal threads of a combined packing and bearing nut 88 which is threaded to the upper end of the casing 90. When the hand wheel, 96 of any valve is appropriately turned the valve may be opened or closed. The nut 98 also serves to compress packing 98 with which each valve is equipped.

With a head constructed in this manner the hydraulic control unit may be employed to operate any one ram or any selected number within its capacity. Selection of the rams to be served by the unit isof course, determined by proper adjustment of the valves 15, 18, 11,," and 19. However, when these valves are open then the pressure which the pump builds up in the main outlet passage? is free to flow to all of the with or in lieu of a typical pipe structure suitable extensions of the head may have intake ducts or passages therein.

Then again, while the head is shown and de scribed asbeing of circular outline, obviously other shapes may be resorted to'and many or the advantages of the invention approximated.

While I have shown and described several constructions in which the invention may be advantageously embodied, it is to be understood that the constructions shown have been selected merely for the purpose of illustration or example and that various changes in the size, shape and arrangement of the parts may be made without departing from the spirit of the invention or the scope of the subjoined claims.

The invention claimed is:

1. A hydraulic power unit of the character described comprising a reservoir having an opening, a closure head releasably secured to the reser- 7 voir and closing saidopening, said head including a marginal attaching flange and a central thickened body portion, said body portion being provided with a central well and aplurality of bores radiating from opposite sides of the well, piston members reciprocable'in said bores, means connecting said pistons, said piston connecting means extending transversely through said well,

said well opening through the external surface of said head, means within said well for supporting an actuating lever for said pistons, said lever supporting means including a ball member, a depending arm carried by the ball and operatively engaging the piston connecting means, and, an operating arm carried by the ball and extending 'exteriorly of said head through the open end of marginal attaching flange and a central thickened body portion, said body portion being provided with a central well and a plurality of bores disposed generally parallel to the plane of the head and communicating at one end with the well at diametrically spaced points, piston members reciprocable insaid bores, means connecting said pistons, said piston connecting means extending transversely through said well, said well opening through the external surface of said head, an upstanding boss surrounding said opening, means within said well and boss for supporting an actuating lever for said pistons, said lever supporting means including a ball member, a depending arm carried by the ball and operatively engaging the piston connecting means, and an operating arm carried by the ball and extending exteriorly of said head through the open end of the well, said thickened body portion of the head being provided with valved intake and discharge passages communicating with saidbores and. with the interior and exterior of said reservoir, respectively, said intake passages including intake pipes carried by the head and terminating adjacent the bottom of the reservoir, said body portion of the head including upstanding web members on the exterior surface thereof extending radially outwardly from said central boas towards said mar- 5 ginal attaching flange, both of said webs being provided with longitudinally extending ducts in communication with each other and with the discharge passages' 01' said bores, one of said ducts serving to deliver the discharge from the bores exteriorly of the reservoir, the other of said ducts being provided with a return passage discharging into the reservoir, and a manually controlled release valve controlling said return passage whereby when said operating lever is oscillated, fluid from within the reservoir may be pumped through the discharge duct when the release valve is closed, or through the return passage when the release valve is open.

3. A hydraulic power unit of the character described comprising a reservoir having an opening, a closure head releasably secured to the reservoir and closing said opening, said head including a marginal attaching. flange anda central thickened body portion, said body portion being provided with a central well and a pair of aligned bores radiating from opposite sides of the well, piston members reciprocable in said bores, means connecting said pistons, said piston connecting means extending transversely through said well, said well opening through the external surface of said head, means within said well for supporting an actuating lever for said pistons, said lever supporting means including a ball member, a depending arm carried by the bail and operatively engaging the piston connecting means, and an operating arm carried by the ball and extending exteriorly of said head through the open end of the well, said thickened body portion of the head being provided with valved intake and discharge passages communicating with said bores and with the interior and exterior of said reservoir, respectively, whereby when the operating arm is oscillated the pistons are reciprocated within their respective bores to pump liquid contained in the reservoir to a point outside thereof, said well being provided with an overflow passage discharging into the reservoir, and located above the 1 level of said cylinder bores, whereby to trap fluid EDWARD M. rmusm. 

